Pump, compressor, and the like



June 15, 1954 Filed Aug. 21 1951 E. F. FORTE PUMP, COMPRESSOR, AND THELIKE 2 Sheets-Sheet 1 Eugn 1 In vex? far 6 Fndnc Parie June 15, 1954 lE. F. PORTE PUMP, COMPRESSOR, AND THE LIKE 2 Sheets-Sheet. 2

Filed Aug. 21 1951 FIG. 2

Patented June 15, 1954 UNITED STATES TENT OFFICE Claims priority,application France October 25, 1950 1 Claim.

The invention is for improvements in or relating to pumps, compressorsand like rotative volumetric machines operating with a continuouscirculation of fluid, that is to say, in which there is practically nopulsation.

The rotative machine according to the inven tion, which may be employedas a liquid pump, a compressor, a vacuum pump or a meter or for anyother purpose, is characterised by the fact that it comprises incombination with a closed casing comprising admission and deliveryducts, and bearings or bearing surfaces for the rotative parts, thefollowing elements:

(a) A rotor substantially in the form of a cylindrical drum subdividedinto two compartments by a partition perpendicular to its axis andconnected to a shaft mounted in bearings in the casing, the said rotorhaving on its periphery two radial blades secured in separatecompartments and disposed at an angle of 180 with respect to oneanother;

(b) Two coaxial bosses of substantially cylindrical form, each situatedin a separate compartment of the rotor and tangentiahy thereto along acommon generatrix, the said bosses being so mounted as to be capable ofturning about their geometrical axis, which is fixed in relation to thecasing, and having on their periphery a slide- Way for engaging thecorresponding blade, means being provided to ensure free orientation ofthe slideway and fluid-tightness between the rotor and each boss oneither side of the corresponding blade;

A set of ports for affording, through the rim of the rotor, theadmission and escape of the fluid into and from the chambers formedbetween the rotor and the bosses and to the rear and in front,respectively, of each blade with respect to' the direction of rotationof the rotor; and

(d) Finally, means for ensuring fluid-tightness between the fluid intakeand delivery ducts.

The invention also concerns a volumetric pump having the aforesaidfeatures and other advan tageous features arising out of a simpleconstruction comprising a small number of parts, most of which aremoulded and machined to afiord the necessary fluid-tightness between thevarious fixed and movable elements by means of an accurate fit betweenthe surfaces in contact. Only two plastic packings, disposed on theshaft of the rotor in the immediate vicinity of the bearings of the saidshaft, are employed.

One embodiment of the invention will now be described with reference tothe drawings, this embodiment being referred to only by way of example.

In the drawings:

Figure 1 is a section taken through the axis of rotation of a pumpaccording to the invention, along the line I-I of Figure 2,

Figure 2 is a section perpendicular to the axis of rotation, taken alongthe line l1-II of Figure 1.

The pump 2! comprises a rotor 22 having the form of a cylindrical drumsub-divided into two symmetrical parts by a partition 23 perpendicularto the axis thereof. A driving shaft 2 is keyed by means of a threadedportion co-aoting with a screwthread 25 in the partition 23 againstwhich a collar 26 bears in a recess of similar form.

The closed casing of the pump 21 comprises two lateral parts 2'? and acentre part 28, the said parts bein bolted together as at 2t and 3E].

The shaft Ed is journalled in hearing in the casing, its free end beingcarried in a thrust bearing 3| comp-rising a ring of rollers 32 whilethe opposite side which extends through the casing is supported by abearing 33 comprising a ring of balls 34. The bearings 31 and 33 aresecured by screws 35 to the parts 21 of the casing. 36 are packing ringsdisposed around the shaft 2% in recesses formed in the casing on theinner side of the bearings 3| and 33.

The parts 2'! of the casing comprise two cylindrical bearing surfaces 31eccentric in relation to the orifice for the passage of the shaft 2 5.38 are anti-friction bearing rings mounted on the said bearing surfaces31. 39 are two cylindrical bosses bored along their axes to enable themto turn about the rings 38 without clearance.

The bosses 39 are fitted with precision against the partition 23 and attheir radial periphery they are tangential to the inner cylindrical wallof the rotor 22 along a generatrix. Thus, there are formed on eitherside of the partition 23 two annular chambers, the cross-section ofwhich has the form of a crescent, the points of which adjoin one another(see Figure 2).

The bosses 39 are maintained laterally on the outer side by an annularpacking 40 which is in turn held in position by a threaded ring 45screwed in a corresponding thread in the rotor 22. The rotor 22 iscapable of turning freely between two neighbouring lateral faces of theparts 27 of the casing, the said neighbouring faces having formedtherein two toroidal recesses 42 communicating through suitable cavitieswith a liquid admission duct 43 (Figure 2) The rotor 22 is providedinternally with two radial blades 44 disposed on either side of thepartition 23 and mounted at with respect to one another. The said blades44 are connected to the rotor by any suitable means. They are shown asbeing fitted in grooves in the rotor 22, in the partition 23 thereof andin the packing ring 48.

A pin 45 slides on each of the blades 44 and each pin is arranged torock freely in a cylindrical recess in the boss 39, the. said recessbeing coaxial with and, along a generatrix, tangent to the said boss. Byvirtue of this arrangement, the rotation of the rotor 22 produces therotation of the bosses 39, the pin 45 sliding against the blade 44 whilerocking freely in its recess in relation to the boss 39. The blade 44 istherefore surrounded or enclosed on its four sides.

48 is an annular centre chamber formed between the part 28 of the casingand the outer surface of the rotor. The chamber 46 communicates with thedelivery duct 41 of the pump. On one side of each blade 44, rotor 22 isprovided with an orifice 48 communicating with the correspondingadmission chamber 42 and an orifice 39 communicating with the deliverychamber 45.

Two valves 58 are pivotally mounted in the chamber 56 on a pin iparallel to the shaft 24. The inner surface of these valves bearstightly against the outer surface of the rotor 22 under the action ofsprings 52. 54 are two metal packing rings consisting of two parts heldbetween the part 28 and the parts 27 of the casing and lodged in twocorresponding grooves in the rotor 22, thus preventing any leakagebetween the chamber 66 and the chambers 42.

Finally, a safety valve 53 is provided between the delivery duct 4! andthe admission duct 43 for protection against excess pressure.

During operation, the pump turns in the direction indicated by thearrows. In Figure 2, the upper blade is shown at the commencement of itsmovement, and assuming a pressure head of liquid in the admission ductthe space between the rotor 22 and the boss 39 connected to the saidblade is filled with liquid through the corresponding orifice 58. Thedelivery orifice E9 is closed by the valve 59. The blade, in advancing,forces the liquid before it without delivering it until the orifice l8situated behind the blade has passed beyond the line of contact betweenthe rotor 22 and the boss 39. At this point, the liquid situated infront of the blade is retained in a closed space, whence it can escapeonly through the discharge orifice 49. The blade delivers liquid untilthe point at which it returns into its starting position. During thissame revolution of the blade, the liquid has been drawn behind itthrough the orifice 4B and the same cycle recommences at eachrevolution. The operation of the blade 54, which is situated at an angleof 180 with respect to the first blade in its compartment (separatedfrom the first compartment by the partition 23) is the same, but itsdelivery is at a maximum when the delivery of the first blade is aminimum. A continuou and practically constant delivery, i. e. withoutany appreciable pulsation, is thus obtained in the delivery duct. Thepump described may in fact be rotated at high speed and the shaft 24 ofthe pump may be directly coupled with the shaft of an electric motor. Ahigh-output motor-driven pump occupying a small amount of space is thusobtained, which is capable of delivery at high pressure. This result isessentially due to the fact that the blades are enclosed on their foursides, whereby all leakage is avoided between the compressed fluid andthe fluid drawn in.

In order to facilitate the explanation of the operation, it has beenassumed that on the inlet side of the pump there is a positive pressurehead, but experiment has shown that a negative pressure of 720 mm. ofmercury can be readily obtained on the suction side and a positivepressure higher than '7 kg. can be obtained on the delivery side,

It will be obvious that various modifications, improvements or additionsmay be made to the embodiment described. In particular, a rotativemachine according to the invention could be provided for use as acompressor for gaseous fluid, with two compression stages, moreespecially by so arranging the partition of the rotor as to form twocompartments of clearly different volume, the larger for the lowpressure and the smaller receiving the compressed fluid at low pressureand compressing it to the final pressure, preferably after cooling.Naturally it would then be necessary to provide fixed fluid circulationducts.

What I claim is:

A rotary machine with continuous circulation of fluid comprising, incombination, a casing, a cylindrical drum disposed in said casing, apartition perpendicular to the axis of said drum dividing said drum intotwo compartments having two lateral walls, a first blade in one of saidcompartments and a second blade in the other of said compartments, saidblades being disposed at an angle of in relation to one another,admission orifices and discharge orifices in said drum on each side ofsaid blades, an inner cylindrical body in each compartment tangential tothe drum and having acavity therein, a cylindrical pin disposed in thecavity of each cylindrical body and tangential thereto, said pin beingformed with a guide-way for receiving the inner edge of a blade, 2.drive shaft coaxial with the drum and secured to said partition,bearings in said casing supporting said drive shaft, a bearing coaxialwith the cylindrical body for supporting said body around said driveshaft and permitting free rotation thereof, circular admission anddischarge channels formed in said casing around said drum, saidadmission orifices and said discharge orifices communicating with saidadmission and discharge channels, respectively, check valves pivoted insaid casing adapted to close the discharge orifices, resilient meansholding said check valves against said drum, and packing means betweensaid drum and said casing separating the admission and dischargechannels.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,941,651 Behlmer Jan. 2, 1934 1,965,388 on; July 3, 1934FOREIGN PATENTS Number Country Date 27,091 Netherlands Jan. 15, 1932

